M5V8

The battery is new and was load tested by AA when they installed. But I can check again. The MAF units have been in the car prob about 5000km now. No issues. Pre cat o2 sensors prob 2000km. Again no issues during this time. I'm not sure what you mean by resetting adaptions. can this be done by disconnecting the battery?

Hi Jon, no i don't think so. I have the peake research tool. I changed the precat 02 & MAF because the car was occasionally stalling out. This solved this issue. Originally the scan only showed bad voltage from post cat 02 sensors which is why i added the spacers in on Ray's advice. I did find some good information last night there is a fuse for the 02 heater system under the cabin air filter box in the engine bay. apparently if this blows you get code 81 & the 02 pre heating system wont work. it is possible the spacer has made the post cat 02 sensor wires short something which I will need to get under the car to confirm. i'll throw this in there too, the alarm randomly went off last wk too. in the garage. No idea if it's related or not.

new rad time. this happened my old e36. luckily for me there was enough left to clamp to so I could get home.

just came back from dinner. freakin did it again. Battery is good. Prob 6 mths old. I'll try the battery disconnect / reset thing tomorrow along with removing the post cat spacers see if that makes a difference. Also I believe there is a heater fuse in the engine bay?

when we got down on the flat I turned off & on and it would rev fine. pulled out accelerated and it went into limp mode again. Turned it off at the next red light. Again as soon as it reved over 3k,..... limp mode. So it would do it over & over. Limp mode literally just got us home. Even in limp mode the motor sounded fine. Got home. Cleared codes. Went for a rip up the road and it's normal again. No sign of any issue. We are out for dinner tonight so I think I will take the M5 for another drive see if it happens again. Very freakin weird. Thing is I don't want to just drop it a Jeff Grey & say find the fault as they might not find anything and hand me a bill for squillions.

i replaced the fuel filter a few weeks ago. But the car was fine all the way over the hill yesterday which is weird. She was out overnight and it got really cold. This is not normal for her. But driving back over the hill she was fine going up, following some grandpa really slowly on the way back down the other side, when to pull out to finally overtake and nothing. Could it be i was driving too slow down a steep hill? but seriously..... maybe a failing fuel pump? or bad gas? can a failing post cat o2 sensor do this kind of thing? I haven't replaced the post cat sensor as I figured this was just to monitor the health of the cats. Could a damaged or short circuit on a sensor cause this issue? I am considering dropping her off to the BMW dealership next week for a full inspection 2 service. She's probably only 5000km off being due anyway.

Help!!!!! Cruising home the M5's gone into limp mode. (not even driving fast at all!! Honest!) Nothing over 3000rpm. No warnings nothing. Turn key off & on its ok. Then almost straight away the same thing. 1/2 tank of gas (always 98) Get home scan Codes: 81 - low fuel cat protection (I think) 58 - post cat o2 voltage (always get this one) 25 - precat 02 heater 26 - precat o2 heater 27- aftercat o2 heater 28 - aftercat o2 heater Reset & go for a drive & it's ok again. What the hell?.. I've got a big drive coming up in two weeks I can afford to have this happen again. Anyone know why the cat system might put the car into limp mode? or is it a fuel pump failing? things done recently: - spacers on the post cat sensors thanks to ray for sourcing them - new fuel filter - new OEM MAF's - replace pre-cat sensors with OEM bosch items (yes i pluged them back in the right way, since I only replaced the pre cats it was pretty easy)

fair call Mitchell. I really hope you build goes smoothly.

Hi mitchell. I can appreciate your point of view and I really hope your build doesn't experience a 10th of the issues that mine did. Yes this might just be my side of the story. However these don't change the facts of the case. Facts that were tabled as evidence in court. 1. they incorrectly sized the head gasket leading to the damage of the first motor 2. they delayed the rebuild of this engine for over a year to claim insurance 3. they returned the car both damaged and unsafe lets just pause for a second on #3. The front suspension was basically not attached to the car anymore. If I had entered an event there was a very real chance of loosing control of the car. I, or worse still, a spectator could have been hurt or killed. I guess it was somekind of luck the turbo issue occurred and this was discovered. 4. when the second engine was damaged they would promise everything, but never did a thing 5. they then attempted to dodge me until I got them in court 6. they also attempted to dodge court not showing up 3 times 7. the ruling is pretty conclusive & overwhelming, I'm more than happy to release this as it's on public record In the end when they couldn't blame the turbo's anymore they blamed "lack" of oil changes when the car had 2 in less than 2000km. They even had the nerve to suggest the car may had done more kms than the speedo showed as I may have 'disconnected' it. I gave them every chance to check the motor themselves(despite 1-3 above), every chance to stand up and correct the problem. They even got a secondary engine report prepared and stuck me with the bill for it. I had months of promises to collect the engine to take it back to their engine builder for analysis. Once in court they then complained that they were denied the ability to take the motor to back to their engine builder. The vital piece of evidence (the oil filter) I handed to them myself and this subsequently was lost. In court they said they never got it. if you have a issue with your work, why would you throw away the one thing that could exonerate you? Are you getting the picture yet? since this i have discovered alot of things about Shred's reputation amongst the industry. 5 years & $28k spent. their work speaks for it'self. 2 engines destroyed and a district court ruling for compensation which so far hasn't been paid. If this happens to you, how will you react?

wait what? there's a battery where?

thanks mate. let me know when it's in & we can meet for coffee or something.

thanks Neal. Yeah i thought of that. But both sets are in the house, in a draw. They wouldn't be able to reach the car anyway. So def not that. Unless someone has something running on the same frequency in the neighbourhood. Wife did say it went off again when the neighbor opened their garage. It's been on trickle charge for a day now, and I haven't heard any complaints from anyone that it's gone off again. hopefully it's solved but I will replace the hood alarm switch just in case

how would i check that? they all lock / unlock fine. nothing in the scan yesterday.

wow. Andy. couldn't be better timing..... could you pick me up one of these? e39 hood alarm trigger - 61-31-9-119-057-M9 priced at $16.00US happy to pickup off you wtgn CBD.

good point. but $16 US isn't exactly breaking the bank. sweet thanks.

well I checked all the doors (they were closed) and checked the hood switch operation seems ok. Did a scan and showed only the usual post cat 02 sensor code which isn't important. Problem is I don't know it's going off as it's locked away snugly in the garage. I'll have to keep an ear out to see if it happens again. I guess anything could have triggered. How much is a replacement hood switch anyways? if it's pennies I'd prefer to just replace and be done with it.

AH hahahahahahahahahahaha...................classic. Yes in the manual. When you goto lock the car. Click the lock key once then quickly hold it down for 3 sec. The "police" light will confirm with a 5 second confirmation light before settling back to flashing. this disables the interior sensors so when you get back to the car and your dogs have been playing musical chairs it's only your hazard lights that were annoying the other shoppers and not the alarm. undercover mission. quote of the day.

terrible pun. just terrible. Battery is fine but I have stuck on charger as it hasn't has a decent drive for at least 3 wks now. Will check the hood switch when I get home. You do know that you can disable the interior sensors for pets?

haha! i'd hope not. But I will check. cheers I've stuck it on a trickle charger in case it's a battery thing. Battery is new (3 mths - ish) so i suspect not. I'll check all the doors & hood are closed properly as just reading it could be that or a faulty hood sensor. Does a scan tell you what triggered?

so the wife calls me this morning as she's leaving and says the BMW's alarm is sounding. thing is it's locked in the garage. She said it went off several times. Once coincided with the neighbour opening his garage. the other coincided with a suspicious red ute & trailor driving slowly up and down our road. She's paranoid. I know. I checked the car. Seems fine. Wasn't sounding when I when down. so strange. what, besides the tilt sensor or interior sensor could trigger the alarm?

my moneys on the fuel pump relay. knock sensors can be triggered with inconsistent fuel pressure to the injectors.

just a guess.... but when I was investigating my issue I read through several posts where they experienced similar problems and it was either the fuel pump, relay or a wiring issue with the pump. I read enough that if my issue wasn't the 02 & MAF sensors I was going to look at the fuel pump next. I think you might be on the right track. my2c

if I had to compare the bills between my racecar and the M5The M5 has been a dream. Regular & preventative maintenance is the key. Fix it before it breaks.

by ambient temp i was meaning the outside temp or more importantly the temperature of the air coming in the front of the car and surrounding the engine. If it was a hot day vs. a cooler one you could have a difference right there. I note on a hot day I can see the temp gauge rise when I pull over and idle for a bit. This either doesn't happen or is less obvious when it's cooler.

there's alot of variables in this too Julian. what was the ambient temp on the two days you are comparing? what was the fuel level or car weight on the two days? was the road the same? & the reading taken at the same spot? man,... I watch too much myth-busters..........